 body{position:relative;display:block;}
      .header{width:100%;height:50px;border-bottom:1px solid grey;background:#4F4F4F;color:white;position:fixed;top:0px;left:0px;z-index:1;min-width:1400px;}
       .header-left{position:absolute;top:15px;left:25px;}
       .text-area{height:28px;border-radius:10px;padding-left:10px;position:absolute;right:290px;width:180px;margin-top:10px;}
       .header-right{margin-top:3px;position:absolute;top:10px;right:20px}
       .header-right span:hover{color:blue;}
       #left{background:#F0F0F0;overflow:scroll;height:100%;width:250px;position:fixed;left:0px;top:52px;}
 #left .title{height:30px;border-bottom:1px solid #000;font-size:17px;margin-top:8px;margin-left:8px;}
 #left ul{line-height:40px;float:left;list-style-type:none;margin:0;padding:0;text-align:left;font-size:12px;}
 #left ul ul{font-size:10px;line-height:24px;margin-left:35px;}

    #left ul li {display: -webkit-flex;
    display: flex;
       -webkit-flex-direction: column;
    flex-direction:column}
     span:hover {
 color: #66B3FF; /*导航栏文字颜色 */
 }
 a {text-decoration:none;color:black;}
  #left ul li a:hover {
 color: #66B3FF; /*导航栏文字颜色 */
 }


 <!--.container{position:relative}-->
 #input-pic{
    <!--background:black;-->
    width:30px;
    height:30px;
    position:absolute;
       right:10px;
       top:5px;
 }
.header-input-pic{
  width:25px;
    height:25px;
    position:absolute;
    right:300px;
    top:15px;
}
.container-item{width:50%;margin-left:35%;}